Multibyte regexps

Ruby
1

I am having some issues with regular expressions when working with
japanese
strings.

Using ruby-1.8.3 on Windows XP home (Japanese version) I have this test:

irb(main):271:0> s = “é??”
=> “\212\223”
irb(main):272:0> l = “è¡?”
=> “\215s”
irb(main):273:0> l =~ /s/
=> 1
irb(main):274:0> puts “#{$}<<#{$&}>>#{$'}" E<s>> => nil irb(main):275:0> "#{$}<<#{$&}>>#{$’}”
=> “\215<>”
irb(main):276:0> s =~ /l/
=> nil

As you can see comparing two totally different characters (kanji) gives
me a
match. Reversing the match gives nil.

How can I get ruby to match things correctly??

regards,
Horacio

2

Hi,

In message “Re: Multibyte regexps…”
on Wed, 21 Dec 2005 18:59:59 +0900, Horacio S.
[email protected] writes:

|I am having some issues with regular expressions when working with japanese
|strings.
|
|Using ruby-1.8.3 on Windows XP home (Japanese version) I have this test:
|
|irb(main):271:0> s = “e$B3se(B”
|=> “\212\223”
|irb(main):272:0> l = “e$B9Te(B”
|=> “\215s”
|irb(main):273:0> l =~ /s/
|=> 1
|irb(main):274:0> puts “#{$}<<#{$&}>>#{$'}" |E<s>> |=> nil |irb(main):275:0> "#{$}<<#{$&}>>#{$'}”
|=> “\215<>”
|irb(main):276:0> s =~ /l/
|=> nil

The encoding seems to be Shift_JIS. You have to specify encoding
before you make regular expression matching. Put s after every
regular expression.

$KCODE=“sjis” # to make p work right
p s = “e$B3se(B”
p l = “e$B9Te(B”
p l =~ /s/s
puts “#{$}<<#{$&}>>#{$'}" p "#{$}<<#{$&}>>#{$'}”
p s =~ /l/s

						matz.
3

Thanks a lot… this seems to work ok.

Where can I find documentation about this $KCODE global var and the “s”
thing
after each regexp? What does the s exactly mean?

Do I have to put it only in regexps with japanese characters or any
regexp? I
tried both and saw no difference.

When using Regexp.new to construct the regular expression how can I set
the s
to the end of it??

sorry for so many questions but I don’t seem to find any docs about
these
options.

Horacio

Wednesday 21 December 2005 21:48e$B!"e(BYukihiro M.
e$B$5$s$O=q$-$^$7$?e(B:

Hi,

In message “Re: Multibyte regexps…”

on Wed, 21 Dec 2005 18:59:59 +0900, Horacio S.

[email protected] writes:

4

I found some documentation about this. Thanks.

Just one question, it seems to me that I can make two different things
to
allow Regexp’s to handle multibyte Shift_JIS strings. One is to set the
$KCODE global variable to “sjis” and the other one is to use the “s”
modifier
when constructing the regular expresion.

The question is do I use only one of the two methods or shall I use the
“s”
modifier even if I set $KCODE to “sjis”??

My testing tells me that only setting the $KCODE global var is enough to
get
Shift_JIS strings and Regexp’s to work correctly but I just want to make
sure.

thanks,
Horacio

Monday 26 December 2005 10:29e$B!"e(BHoracio S.
e$B$5$s$O=q$-$^$7$?e(B:

5

l =~ /s/ ??

It will try to find a char “s” in string l and not the value remained
in variable s.

Horacio S. [email protected] wrote:

I am having some issues with regular expressions when working with
japanese
strings.

Using ruby-1.8.3 on Windows XP home (Japanese version) I have this test:

irb(main):271:0> s = “éÂ?Â?”
=> “\212\223”
irb(main):272:0> l = “è¡Â?”
=> “\215s”
irb(main):273:0> l =~ /s/
=> 1
irb(main):274:0> puts “#{$}<<#{$&}>>#{$'}" E> => nil irb(main):275:0> "#{$}<<#{$&}>>#{$'}”
=> “\215<>”
irb(main):276:0> s =~ /l/
=> nil

As you can see comparing two totally different characters (kanji) gives
me a
match. Reversing the match gives nil.

How can I get ruby to match things correctly??

regards,
Horacio